Al-Al_6Mn 共晶合金의 一方向凝固 = Unidirectional Solidification of Al-Al_6 Mn Eutectic Alloy

국문 초록 (Abstract)

Al-Al_6Mn 共晶合金을 凝固速度 0.01∼0.12㎝/min까지 變化시켜 一方向凝固시켰을 때 composite의 組織, 機械的 性質, Ni 添加에 의한 영향 및 凝固速度의 變化를 調査하여 얻어낸 結果는 다음과 같다.
1. 凝固速度가 增加함에 따라 나타나는 composite組織은 Al-Al_6Mn 共晶合金은 blade type에서 square pillar type으로, Al-Al_6Mn 共晶에 Ni를 添加한 경우는 blade type에서 rod와 square pillar type이 공존하는 composite로 變化되었다.
2. 相間隔은 凝固速度가 增加함에 따라 減少하였으며 相間隔의 역수와 凝固速度의 평방근사이에는 직선적인 關係가 이루어졌다.
3. 凝固速度가 增加함에 따라 引張强度가 增加하였다.

다국어 초록 (Multilingual Abstract)

Al-Al_6Mn eutectic composite have been prepared by unidirectional solidification at solidification rate range from 0.01 to 0.12㎝/min. The effects of the solidification rate and the addition of nikel on the composite structure and the mechanical properties were investigated.
The results obtained are as follows.
1. As the solidification rate increased, the morphology of the composite structures changed from the blade type into the square pillar type in Al-Al_6Mn composite, but from the blade type into the mix type of rod and the square pillar in Al-Al_6Mn-Al_3Ni composite.
2. The interphase spacing decreased with the increase of solidification rate. The reciprocal of the interphase spacings were linearly propotinal to the square root of the solidification rate.
3. The increased solidification rate resulted in the higher mechanical strength.